Volatiles from submerged macrophytes in a large meso-oligotrophic lake

The release of volatile organic compounds (VOCs) from freshwater macrophytes has received limited attention. Here, we used an exploratory approach to quantify net VOC release rates and their chemical diversity in submerged macrophyte species collected from an alpine lake (Lake Geneva, France). Holobionts of Myriophyllum spicatum , Potamogeton perfoliatus, and Potamogeton lucens were co-incubated and VOCs were analysed using a purpose-built purge-and-trap system followed by gas chromatography-mass spectrometry. In addition, Lagarosiphon major was individually incubated. The mean total net VOC release rates ranged from 397 to 1142 pmol g −1 DW h −1 . Hydrocarbons and monoterpenoids accounted for 60–70% of the total net VOC release. Release of ketones and aldehydes as well as monoterpenoids and sesquiterpenoids varied between the co-incubated species. The macrophyte volatilomes consisted of both common and unique VOCs. This interspecific variability suggests that biodiversity but also temporal and spatial dynamics and environmental controls may affect the release of VOCs from macrophytes and their contributions to VOC fluxes in freshwater ecosystems.